Offline Self-Commissioning Method to Estimate Direct & Quadrature Axes Inductance for IPM/SPM in Industrial Motor Drive Applications

This paper proposes a sensor-less control method to estimate direct and quadrature axes inductance for both interior and surface mount permanent magnet motor (IPM/SPM). The proposed method determines inductance by applying square-wave voltages along the d and q axes and analyzing the resulting flux map. A DC current is used to lock the rotor, minimizing position error. This offline method of estimation can be used for self-commissioning of both IPM/SPM motors in the field by industrial motor drives. Experimental tests on a 22 kW IPM prove the validity of the proposed method.